Description

The rdist utility maintains copies of files on multiple hosts. It preserves
the owner, group, mode, and modification time of the master copies, and
can update programs that are executing. (rdist does not propagate ownership or
mode changes when the file contents have not changed.) Normally, a copy on
a remote host is updated if its size or modification time differs
from the original on the local host. With the -y option (younger
mode), only the modification times are checked, not the size. See OPTIONS
below.

There are two forms of the rdist command. In the first form
shown in the SYNOPSIS section above, rdist reads the indicated distfile for
instructions on updating files and/or directories. If distfile is `-', the standard
input is used. If no -f option is present, rdist first looks
in its working directory for distfile, and then for Distfile, for instructions.

The second form shown in SYNOPSIS uses the -c option and specifies
paths as command line options.

The user can opt for a secure session of rdist which uses
Kerberos V5 for authentication. Encryption of the data being transferred is also
possible. The rdist session can be kerberized using any of the following
Kerberos specific options : -a, -PN or -PO, -x, and -krealm.
Some of these options (-a, -x, -PN or -PO, and -f or
-F) can also be specified in the [appdefaults] section of krb5.conf(4). The
usage of these options and the expected behavior is discussed in the
OPTIONS section below. If Kerberos authentication is used, authorization to the account is
controlled by rules in krb5_auth_rules(5). If this authorization fails, fallback to normal
rdist using rhosts occurs only if the -PO option is used explicitly
on the command line or is specified in krb5.conf(4). Also notice that the
-PN or -PO, -x, and -krealm options are just supersets of
the -a option. In order to use the non-secure version of rdist
across machines, each host machine must have a /etc/host.equiv file, or the user
must have an entry in the .rhosts file in the home directory.
See hosts.equiv(4) for more information.

Options

The following options are supported:

-a

This option explicitly enables Kerberos authentication and trusts the .k5login file for access-control. If the authorization check by in.rshd(1M) on the server-side succeeds and if the .k5login file permits access, the user is allowed to carry out the rdist transfer.

-b

Binary comparison. Performs a binary comparison and updates files if they differ, rather than merely comparing dates and sizes.

-cpathname . . .[login @]hostname[:destpath ]

Copies each pathname to the named host; if destpath is specified, it does not update any pathname on the named host. (Relative filenames are taken as relative to your home directory.) If the `login @' prefix is given, the update is performed with the user ID of login. If the `:destpath' is given, the remote file is installed as that pathname.

-dmacro=value

Defines macro to have value. This option is used to define or override macro definitions in the distfile. value can be the empty string, one name, or a list of names surrounded by parentheses and separated by white space.

-D

Enables debugging.

-fdistfile

Uses the description file distfile. A `-' as the distfile argument denotes the standard input.

-h

Follows symbolic links. Copies the file that the link points to rather than the link itself.

-i

Ignores unresolved links. rdist normally tries to maintain the link structure of files being transferred and warn the user if all the links cannot be found.

-krealm

Causes rdist to obtain tickets for the remote host in realm instead of the remote host's realm as determined by krb5.conf(4).

-K

This option explicitly disables Kerberos authentication. It can be used to override the autologin variable in krb5.conf(4).

-mhost

Limits which machines are to be updated. Multiple -m arguments can be given to limit updates to a subset of the hosts listed in the distfile.

-n

Prints the commands without executing them. This option is useful for debugging a distfile.

-PO

-PN

Explicitly requests new (-PN) or old (-PO) version of the Kerberos “rcmd” protocol. The new protocol avoids many security problems prevalant in the old one and is regarded much more secure, but is not interoperable with older (MIT/SEAM) servers. The new protocol is used by default, unless explicitly specified using these options or through krb5.conf(4). If Kerberos authorization fails when using the old “rcmd” protocol, there is fallback to regular, non-kerberized rdist. This is not the case when the new, more secure “rcmd” protocol is used.

-q

Quiet mode. Does not display the files being updated on the standard output.

-R

Removes extraneous files. If a directory is being updated, removes files on the remote host that do not correspond to those in the master (local) directory. This is useful for maintaining truly identical copies of directories.

-v

Verifies that the files are up to date on all the hosts. Any files that are out of date are displayed, but no files are updated, nor is any mail sent.

-w

Whole mode. The whole file name is appended to the destination directory name. Normally, only the last component of a name is used when renaming files. This preserves the directory structure of the files being copied, instead of flattening the directory structure. For instance, renaming a list of files such as dir1/dir2 to dir3 would create files dir3/dir1 and dir3/dir2 instead of dir3 and dir3. When the -w option is used with a filename that begins with ~, everything except the home directory is appended to the destination name.

-x

Causes the information transferred between hosts to be encrypted. Notice that the command is sent unencrypted to the remote system. All subsequent transfers are encrypted.

-y

Younger mode. Does not update remote copies that are younger than the master copy, but issues a warning message instead. Only modification times are checked. No comparison of size is made.

Usage

White Space Characters

NEWLINE, TAB, and SPACE characters are all treated as white space; a
mapping continues across input lines until the start of the next mapping:
either a single filename followed by a `->' or the opening parenthesis of
a filename list.

Comments

Comments begin with # and end with a NEWLINE.

Distfiles

The distfile contains a sequence of entries that specify the files to
be copied, the destination files to be copied, the destination hosts, and
what operations to perform to do the updating. Each entry has one
of the following formats:

The first format is used for defining variables. The second format is
used for distributing files to other hosts. The third format is used
for making lists of files that have been changed since some given
date. The source list specifies a list of files and/or directories on
the local host that are to be used as the master copy for
distribution. The destination list is the list of hosts to which these
files are to be copied. Each file in the source list is
added to a list of changes if the file is out of
date on the host that is being updated (second format) or if
the file is newer than the time stamp file (third format). Labels are
optional. They are used to identify a command for partial updates. The
colon (:) is used after an optional label, while the double colon
(::) is used for making lists of files that have been changed
since a certain date (specified by the date/time of the time_stamp file). Typically,
only notify is used with the '::' format of the command line.

Macros

rdist has a limited macro facility. Macros are only expanded in filename
or hostname lists, and in the argument lists of certain primitives. Macros
cannot be used to stand for primitives or their options, or the
`->' or `::' symbols.

A macro definition is a line of the form:

macro=value

A macro reference is a string of the form:

${macro}

although (as with make(1S)) the braces can be omitted if the macro
name consists of just one character.

Kerberos Access-Control file

For the kerberized rdist session, each user might have a private authorization
list in a file .k5login in their home directory. Each line in
this file should contain a Kerberos principal name of the form principal/instance@realm.
If there is a ~/.k5login file, then access is granted to the
account if and only if the originater user is authenticated to one
of the principals named in the ~/.k5login file. Otherwise, the originating user is
granted access to the account if and only if the authenticated principal
name of the user can be mapped to the local account name
using the authenticated-principal-name -> local-user-name mapping rules. The .k5login file (for access control)
comes into play only when Kerberos authentication is being done.

Metacharacters

The shell meta-characters: [, ], {, }, * and ? are recognized
and expanded (on the local host only) just as they are with
csh(1). Metacharacters can be escaped by prepending a backslash.

The ~ character is also expanded in the same way as with
csh; however, it is expanded separately on the local and destination hosts.

Filenames

File names that do not begin with ` / ' or ` ~ ' are taken
to be relative to user's home directory on each destination host; they
are not relative to the current working directory. Multiple file names must be
enclosed within parentheses.

Primitives

The following primitives can be used to specify actions rdist is to
take when updating remote copies of each file.

install [-b] [-h] [-i] [-R] [-v] [-w] [-y] [newname]

Copy out of date files and directories (recursively). If no newname operand is given, the name of the local file is given to the remote host's copy. If absent from the remote host, parent directories in a filename's path are created. To help prevent disasters, a non-empty directory on a target host is not replaced with a regular file or a symbolic link by rdist. However, when using the -R option, a non-empty directory is removed if the corresponding filename is completely absent on the master host.

The options for install have the same semantics as their command line counterparts, but are limited in scope to a particular map. The login name used on the destination host is the same as the local host unless the destination name is of the format login@host. In that case, the update is performed under the username login.

notifyaddress. . .

Send mail to the indicated email address of the form:

user@host

that lists the files updated and any errors that might have occurred. If an address does not contain a `@host ' suffix, rdist uses the name of the destination host to complete the address.

exceptfilename . . .

Omit from updates the files named as arguments.

except_patpattern . . .

Omit from updates the filenames that match each regular-expression pattern (see ed(1) for more information on regular expressions). Note that `\' and `$' characters must be escaped in the distfile. Shell variables can also be used within a pattern, however shell filename expansion is not supported.

special [filename] . . . "command-line "

Specify a Bourne shell, sh(1) command line to execute on the remote host after each named file is updated. If no filename argument is present, the command-line is performed for every updated file, with the shell variable FILE set to the file's name on the local host. The quotation marks allow command-line to span input lines in the distfile; multiple shell commands must be separated by semicolons (;).

The default working directory for the shell executing each command-line is the user's home directory on the remote host.

IPv6

The rdist command is IPv6–enabled. See ip6(7P). IPv6 is not currently supported
with Kerberos V5 authentication.

Examples

Example 1 A Sample distfile

The following sample distfile instructs rdist to maintain identical copies of a
shared library, a shared-library initialized data file, several include files, and a
directory, on hosts named hermes and magus. On magus, commands are executed as
super-user. rdist notifies merlin@druid whenever it discovers that a local file has
changed relative to a timestamp file. (Parentheses are used when the source
or destination list contains zero or more names separated by white-space.)